ORBITA-AF Feasibility trial
Research type
Research Study
Full title
ORBITA-AF feasibility trial: Objective Randomised Blinded Investigation of Therapeutic Ablation versus cardioversion for persistent Atrial Fibrillation (ORBITA-AF)
IRAS ID
237038
Contact name
Richard Schilling
Contact email
Sponsor organisation
Barts Health NHS Trust
Clinicaltrials.gov Identifier
Duration of Study in the UK
1 years, 0 months, 1 days
Research summary
Research summary:
To date, there are no randomised, double-blinded clinical trials comparing catheter ablation to DC-cardioversion(DCCV) with medical therapy in patients with persistent atrial fibrillation(PersAF). Conducting a large-scale trial to address this question presents considerable challenges, including recruitment, blinding, and implementation. We conducted a pilot study to evaluate the feasibility of conducting a definitive placebo-controlled trial.
Methods:
This prospective trial was carried out at Barts Heart Centre, UK, employing a randomized, double-blinded, placebo-controlled design. Twenty patients with PersAF (duration <2years) were recruited, representing 10% of the proposed larger trial as determined by a power calculation. The patients were randomized in a 1:1 ratio to receive either PVI±DCCV(PVI group) or DCCV+Placebo(DCCV group). The primary endpoint of this feasibility study was to evaluate patient blinding. Patients remained unaware of their treatment allocation until end of study.Atrial Fibrillation (AF) is the commonest cardiac arrhythmia and a major cause of stroke. Until recently patients with AF were often referred for cardioversion (an electric shock procedure to try to re-establish a normal heart rhythm). However,a newer technique of catheter ablation which aims to isolate the pulmonary vein using cryoablation has resulted in significantly less AF after treatment as well as symptom improvement and increased quality of life. There has been no blinded trial to compare these two procedures to see which one is better. The results from such a trial could transform the care of our patients by providing an evidence base to guide treatment choices.
We seek to perform a blinded, randomised trial comparing electrical caridoversion with a pulmonary vein isolation strategy for the treatment of persistent AF. We have developed a detailed protocol for this trial, but also wish to initially perform a pilot study to prove feasibility of the study. The pilot study will allow us to work out the best way of performing the trial, particularly the way in which we will deal with 'blinding' the patients and medical teams to which procedure the patient has been allocated to.
Summary of results:
During the study, 35% of patients experienced recurrence of PersAF prior to completion of 12 months follow-up. Blinding was successfully maintained amongst both patients and medical staff. The DCCV group had a trend to higher recurrence and repeat procedure rate compared to the PVI group (recurrence of PersAF 60 %vs 30%; p=0.07 and repeat procedure 70% vs 40%;p=0.4). Quality-of-life improved in the PVI group in terms of AF specific questionnaire [AF PROMS] score improvement [23(±22) vs 2(±10); p<0.001] and SF-12 mental-component raw score [ 11.83(±11) vs -8.54(±11.5); p=0.017] at 12 months.
Conclusion:
This feasibility study establishes the potential for conducting a blinded, placebo-controlled trial to evaluate the efficacy of PVI versus DCCV in patients with PersAF.
https://gbr01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fu2790089.ct.sendgrid.net%2Fls%2Fclick%3Fupn%3DXv3JSvJ-2B3M71ppf7N9agbapvbma-2FSP4E8Oa28SzxMdVVQ-2BqwXW7rRx2J-2FJQzo8yhzq6Mf56Dn1ilt4a1soE4Ae3JacjLZ0pECdcXjKu-2B04hSFfYrHDFDyHi2V2z08MIwnxUM-2FaVCPlIQSlPmherRszmBYv-2BRzLro2OtVghzMGl4qaGKbEzOMd4euuDxN4hf6QQhLrw8jpAutcBwc-2FE8NGA-3D-3Dka0k_E1aO2-2BZlVOSJJV-2FajQqskegTd6IRomHYTi-2Fbt8SH3YKrLgBR9bmqwF4dDiuPrvlsYm67HTFGsNw3M1rb8gi-2FEh49kJnliX0lxbjMLb0jXPWY5GOkqMvp6dtzM0pkqfZlaM3pnTgNnqFR0qaOGBYBnX2KlCSrh7SsDEwhyep8dpg4-2BI6iw7gZDrDsYHEKMXDoNxuBaabfDEj1GfWSGPzB1A-3D-3D&data=05%7C02%7Charrow.rec%40hra.nhs.uk%7C3051daf2dc314f83b2f508dc0d44cfed%7C8e1f0acad87d4f20939e36243d574267%7C0%7C0%7C638399836391650433%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=o4JeAQBJNDmZct4gB2f9h44054nbmjBfETOLI1XXUC0%3D&reserved=0
REC name
London - Harrow Research Ethics Committee
REC reference
19/LO/0775
Date of REC Opinion
28 Oct 2019
REC opinion
Further Information Favourable Opinion